Since the heaviest snow was confined to a fairly small, but very heavily populated area, the storm was only ranked as a low-end Category 3 (Major) on the new Northeast Snowfall Impact Scale, which takes into account the area and population affected, as well as snowfall accumulations.[2] This indirectly also reflects the fact that casualties were extremely low and cleanup was fairly quick, even in the New York City area where the record snow amounts occurred. The main reasons for this are: A) The storm fell on a Sunday when many people can more easily stay home, B) the relatively small geographic area of extremely large snowfall, and C) Because the temperature was well below freezing throughout most of the storm, the snow was mostly dry and light in composition, as opposed to the wet and heavy snows that make some otherwise lesser storms much harder to clean up from and are more common at least in the coastal Northeast. Additionally, temperatures in the days after the storm were unseasonably warm in some spots (reaching the mid-50s °F in hard-hit New York City, and the mid 60s in DC) which helped melt the snow much more quickly than usual.

The storm system began developing on February 11 as a relatively minor system, bringing some snow along the southern Appalachian range. The low pressure center moved off-shore early February 12 before it began its rapid intensification. By early morning, snow began falling heavily, taking several forecasters by surprise who had expected about a foot of snow, at most, along the eastern fringes of the Atlantic seaboard. During the height of the storm on Sunday morning the 12th, thunder and lightning occurred as the snow fell. The presence of this thundersnow shows how energetic this storm became.

The extreme intensification was partially the result of a fairly mild winter that kept water temperatures in the Atlantic a few degrees warmer than they normally are in February. The storm system's intensity led to snowfall accumulations upwards of 32 inches (81.3 cm) in some localities.

In addition to the heavy snow, coastal flooding from storm surge was reported, particularly in Massachusetts.[3] Storm surges have been recorded as high as 3 feet (1 m) in parts of New England.[4]

The low pressure area began forming in the Southern states a few days prior to the Blizzard striking, eventually merging with a northern stream system. A trough on the East Coast brought the system up the coast, and cold high pressure to the north eventually slowed the system to a crawl. As the system completed bombing, or rapid decrease in central pressure (a common measure of the strength of a storm), mesoscale banding features (areas of significant snowfall associated with smaller scale physical phenomena) impinged on the entire I-95 Corridor.

The low pressure center was so deep that somewhat of an eye actually formed. Rarely do eyes form on storms other than hurricanes, and it is especially rare in extratropical cyclones. NASA took a satellite picture of the eye of the storm; the eye was located south and east of southern New Jersey in this picture.

Three casualties occurred as a result of the snow: in Virginia, a man died due to his truck sliding off a highway; in Baltimore, a person died in a house fire as a result of snow delaying rescue workers from getting to the fire.[5] A third fatality occurred in a weather-related accident in Nova Scotia.[6]

While Connecticut was one of the hardest hit areas, the state was well-prepared for the storm and managed to avoid major problems. Hartford received a total of 21.9 inches (55 cm) of snow — the second largest snowfall since 1906. A total of 18 inches (46 cm) fell in the small Sandy Hook village.[7]West Hartford totaled 27 inches (69 cm) and Fairfield saw 27.8 inches (70.6 cm) of snow. Despite the large amounts of snow, there were only isolated individual power outages. At the storm's onset, governor M. Jodi Rell ordered all tractor-trailer trucks off the state's highways to facilitate the efforts of highway crews with snow removal. Motorists whose vehicles were not equipped with 4-wheel drive were required to use snow chains to travel on state roadways during the storm. Connecticut mobilized 2,500 state-owned and privately contracted snowplows to keep state highways open during the storm. The state's 169 cities and towns employed hundreds of additional plows to keep local roads passable. Bradley International Airport was closed for several hours, and the storm disrupted service on Metro North.

New Castle County and Wilmington felt the brunt of this storm, with 14–15 inches (35–38 cm) of snow. Kent and Sussex counties to the south mixed with rain for a while, and saw significantly less snow accumulations, mostly in the 6 inch (15 cm) range.

The heaviest snow in Maryland fell from the northern suburbs of Washington, D.C., to the Baltimore area. These areas overwhelmingly saw over a foot of snow. Snowfall rates of 2–3 inches (5–8 cm) per hour were common, and thundersnow occurred. Snowfall amounts of up to 21 inches (53 cm) were reported in Columbia, 13.1 inches (33.3 cm) in Baltimore, 17 inches (43 cm) in Catonsville, and a foot (30.5 cm) in Potomac. This was the area's heaviest snow since the North American blizzard of 2003. Lesser amounts occurred in western and southern parts of the state.

The most serious coastal problems were in Massachusetts. The heaviest snow was in the central part of the state, where snow amounts of up to 20 inches (50 cm) were reported. Coastal areas, particularly around Nantucket, saw lesser amounts (approximately 12") as it was mixed with sleet at times, but winds of up to 60 mph (95 km/h) whipped up the ocean with storm surges of 2 to 3 feet (60 to 90 cm) and led to some coastal flooding, plus offshore waves of up to 25 feet (8 m). Logan International Airport in Boston and Barnstable municipal airport in Hyannis on Cape Cod saw over 90% of their flights cancelled at the peak of the storm.

There were no power outages, despite the conditions.[9] There was one death; a tree fell onto a pickup truck in Billerica, killing the driver.[10] Strong winds across the state caused $1.9 million in damage (2006 USD).[11]

The impact of the blizzard in northern New Jersey was strong enough to stop the New Jersey Transitbus service between 7:30 a.m. and 4:00 p.m., although trains continued to run (with some delays).[12] Many roads remained closed. Businesses were closed for most of the day. 16,000 people were without power in the state. Central and northeastern New Jersey saw the brunt of the storm due to heavy banding through the night into the morning: 21" (53.3 cm) of snow fell at Newark Airport and 27" fell in Rahway. The first Wicked Faire took place as scheduled.

Central Park received 26.9 inches (68.3 cm) of snow, the largest amount for a single storm since records began, breaking the record of 26.4 inches (67.1 cm) that fell on December 26, 1947. By comparison, the blizzards of 1996and 2003 dropped 20.2 and 19.8 inches (51.3 and 50.3 cm) in Central Park respectively. The smallest amounts of snowfall were recorded in portions of Nassau County, including the towns of Oceanside, Lynbrook, Rockville Centre and Island Park. The snow removal cost in New York City alone is estimated at about $27 million.[13] It took nearly two days for utility crews to fully restore service to as many as 300,000 customers.[10]

The storm did not reach very far north of the city; the Albany area only received 1–2 inches (2.5–5 cm) of snow. As a result, the 2005–06 winter season ended up being the first time ever since records began in the late 19th century that New York City received more snow than Albany in a given winter (the inland, upstate city averages about twice as much snowfall per winter as its big neighbor to the south).

The strong winds downed trees and powerlines, resulting in $3 million in damage (2006 USD).[11] The Long Island Rail Road reported extensive delays and as many as eight trains disabled up to several hours after the blizzard. The Monday morning commute was no better, as two of the railroad's lines were shut down completely and delays caused headaches for ambitious commuters. By Tuesday, two days after the storm, service was back to normal.[14]

Despite the record snowfall, the New York City schools were open on February 13, owing to planning and work by the city and its snowplow team.

Snowfall totals were measured at 12 inches (30 cm) at Philadelphia International Airport, but 35 miles (56 km) to the west in West Caln Township, there were 21 inches (53 cm). Philadelphia International Airport remained open throughout the storm, although about 50% of flights were cancelled. There were also power outages in the Philadelphia area, with about 10,000 customers losing power. But in contrast, in Western Pennsylvania most got 1" (2.5 cm) or less of snow.[15] Philadelphia public and parchocial schools were closed for the day.[16]

According to Dominion Power, over 64,000 people in Northern Virginia lost power in the storm, primarily in the suburban areas adjacent to Washington, D.C.[8] Many locations in the extreme northeastern portion of the state recorded 10–15" (25–38 cm) of snow, with Falls Church and Fairfax coming in at 13.5" (34.3 cm) and 14.0" (35.6 cm) respectively. Fairfax County and eastern Loudoun County were generally the start of the 12+" (30+ cm) accumulations, which spread north towards Massachusetts.

While the snowfall amounts diminished somewhat (to about 6 to 12 inches (300 mm) or 15 to 30 cm) by the time the storm tracked east into Atlantic Canada, the winds increased substantially. The worst of the storm was felt along the Atlantic coast, particularly in a swath around the Bay of Fundy, the Northumberland Strait and the south coast of Newfoundland. Hurricane-force wind gusts were reported in several communities, peaking at 156 km/h (97 mph) in Grand Etang, Nova Scotia (equal to a Category 2 hurricane) and 133 km/h (83 mph) in Cape Race on the east coast of Newfoundland. Some damage was reported as a result of the strong winds, particularly downed power lines but also some roof damage to buildings.